By way of reference, it is recalled that electrical machines include synchronous machines, asynchronous machines, and variable reluctance machines.
The principles on which those various types of machines operate are very different, and as a result the person so skilled in the art would not envisage transposing solutions known for one of those types of machine to another of those types.
Thus, it should be observed that a synchronous machine, to which the present invention relates, differs from a variable reluctance machine in the following respects:
the size of the stator teeth overlapping a rotor half-tooth; PA1 the presence of a stator primary (or "field") winding in which no back-emf is induced by rotation; PA1 the bipolar nature of the field in the teeth of the rotor; and PA1 the single phase structure of each of the "pancakes" of the rotor. PA1 the magnetizing means comprise at least one primary winding received in the notches of the stator; PA1 each of the stator and the rotor has a plurality of stages, each of the stator stages receiving a secondary winding corresponding to one of the phases of the machine; PA1 the notches of the various stages of the rotor are, from one stage to another, offset angularly by the width between two notches divided by the number of stages; PA1 the notches of the various stages of the rotor are distributed thereon without angular offset from one stage to another, said stator having an inductor winding wound over its full height and common to its various stages; and PA1 the secondary windings of the various stages are wound in corresponding manner on the notches of the stator without angular offset from one stage to another.
The synchronous machine of the invention can be used both as a generator of electricity and as an electric motor.
In particular, it is advantageously used in a motor vehicle where it serves both as an alternator and as an electric motor for starting, the rotor of the machine being directly mounted on the shaft of the vehicle engine.
In such a configuration, it is desirable for the rotor of the synchronous machine to be as well balanced as possible, and to avoid it having any permanent magnets or coils.